Pressure flow study: a useful diagnostic test of female lower urinary tract symptoms

AIMS: To compare pressure flow parameters in the different urodynamic diagnoses in women with lower urinary tract symptoms (LUTS). MATERIALS AND METHODS: Urodynamic traces of women with LUTS were prospectively studied. Detrusor pressures at the start of flow (ODP), detrusor pressure at peak flow rate (PdetQmax), peak flow rate (Qmax) and detrusor pressure at the end of flow (CDP) were measured and compared with different urodynamic diagnoses. RESULTS: Six hundred and twenty one women were prospectively investigated between September 2000 and February 2002. Only 85% (529/621) of women had good quality pressure flow studies and was included in the study. Women with detrusor overactivity have higher ODP, CDP and PdetQmax than women with urethral sphincter incompetence. All these pressure flow parameters are significantly lower in women with urethral sphincter incompetence than continent women (P < 0.05, Bonferroni test). Qmax was significantly greater in women with urodynamic stress incontinence compared to women who had detrusor overactivity (P < 0.05, Bonferroni test). Women with mixed incontinence had pressure flow parameters intermediate between women with detrusor overactivity and those with urodynamic stress incontinence. CONCLUSIONS: Pressure flow parameters appear to be useful urodynamic tools in the evaluation of women with LUTS as they help the clinician in assessing the urethral and detrusor function.